How can you tell if your intake is leaking?

9

90blue5.0

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Apr 4, 2004

#1

• Apr 4, 2004

• #1

My car stumbles in idle and the exhaust smells rich. This is after I put a systemax intake and some ported heads, the only part that really bothers me is the stumbling, could the intake be causing this or could there be anything else that would couse this after that type of workk is done?

 

5.0Droptop

...all those nights we shared, and you're a dude??

Special Agent Mukity-Muck Whats in Charge Round Here

May 15, 2002

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Apr 4, 2004

#2

• Apr 4, 2004

• #2

did you reset the idel and tps make sure you have no vac leaks etc?

 

5.0Droptop

...all those nights we shared, and you're a dude??

Special Agent Mukity-Muck Whats in Charge Round Here

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#3

• Apr 4, 2004

• #3

http://www.50tech.com/articles/display_article.php?catid=9&id=10

http://www.50tech.com/articles/display_article.php?catid=8&id=4

 

90mustangGT

I felt sorry for girls because

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Jan 15, 2002

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89

Dallas, GA

Apr 4, 2004

#4

• Apr 4, 2004

• #4

Spray carb/intake cleaner where you think it may be leaking, such as around the TB or where the intake meets the heads. If the stumbling stops, it tells you that is where the leak is. The cleaners will cover the leak tempararly. You want to use something flamable if there is a leak, some of it will be sucked in, and if it isn't flamable then it won't burn, makeing a misfire, so you won't be able to detect the leak. I work in a shop and this is how we do it.

 

5.0Droptop

...all those nights we shared, and you're a dude??

Special Agent Mukity-Muck Whats in Charge Round Here

May 15, 2002

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Apr 4, 2004

#5

• Apr 4, 2004

• #5

Also have you tried pulling codes?

 

Z

ZarnAutomotive

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Aug 12, 2003

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Apr 4, 2004

#6

• Apr 4, 2004

• #6

do a vacum test

 

9

90blue5.0

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Apr 4, 2004

#7

• Apr 4, 2004

• #7

no, havent puled any codes yet but will maybe try that this afternoon.

 

9

90blue5.0

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Apr 4, 2004

#8

• Apr 4, 2004

• #8

What is the best way to do a vacume test?

 

dastang2

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Dec 11, 2003

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tx

Apr 4, 2004

#9

• Apr 4, 2004

• #9

your car would be running lean actually but the computer sends more fuel to make up for the problem.

 

dastang2

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Dec 11, 2003

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tx

Apr 4, 2004

#10

• Apr 4, 2004

• #10

so then it would be rich.

 

9

90blue5.0

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Apr 4, 2004

#11

• Apr 4, 2004

• #11

Yes, more fuel = rich.

 

HISSIN50

"How long does it take to get help in here?

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#12

• Apr 4, 2004

• #12

motor with a stock cam should pull around 15-20 inches of vac at idle. if you have a more radical cam, well you can see half of that. it all depends on the cam.
grab a port on the tree on the driver side firewall and see whatcha got.
the 88 (SD) had an extra port for my gauge.
good luck.

 

9

90blue5.0

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Apr 5, 2004

#13

• Apr 5, 2004

• #13

So I set the TPS to .97 and checked the vac which showed about 17 inches, the TPS had no effect of anything and I still haven't checked codes but maybe today I will. Is that 17 inches normal at idle??

 

HISSIN50

"How long does it take to get help in here?

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Apr 6, 2004

#14

• Apr 6, 2004

• #14

17 inches sounds good to me.

 

D

D347643

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Apr 6, 2004

#15

• Apr 6, 2004

• #15

not to hijack the thread but i just installed my trick flow stage 1 cam and im only running 13-14 inches...is that normal?

Drew

 

HISSIN50

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#16

• Apr 6, 2004

• #16

Drew, im good on stock or near stock stuff, but not so much on aftermarket items. most aftermarket cams pull less vac than stockers (hence the reason SD guys cant go nuts on the cams - they loose too much vac, which messes things up).

im no expert, but i would bet that your vac is just fine. that is almost near stock levels, which many dont even have with a stock set up (leaks and worn internals).

enjoy the new bits!

 

9

90blue5.0

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Apr 6, 2004

#17

• Apr 6, 2004

• #17

So yesterday I adjusted my TPS and today it won't idle, adjusted it to .97 and now it will idle for a few seconds then dip down to almost die and shoot back up repeatedly. WTF is wrong now?

 

66 Tiger

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Jul 13, 2003

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Virginia

Apr 6, 2004

#18

• Apr 6, 2004

• #18

90blue5.0 said:

So yesterday I adjusted my TPS and today it won't idle, adjusted it to .97 and now it will idle for a few seconds then dip down to almost die and shoot back up repeatedly. WTF is wrong now?

Click to expand...

Did you change out throttle bodies? When I changed all my stuff out, I was having the same probs. I checked all the same stuff & still no idle. Eventually I figured it out... I didn't adjust the idle on the new TB! Funny now, but I was pretty PO at the time!

 

HISSIN50

"How long does it take to get help in here?

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#19

• Apr 6, 2004

• #19

what is your idle set at? once you start playing with idle sensor stuff, it is a good idea to check it all. i.e., if you play with the idle set screw, you should re-adjust the TPS. now i dont think you did; just some general info for future reference.

what is your timing set at? just went through this with an S-10 (4.3L). the dizzy set bolt had worked loose and timing had become like me, retarded. truck ran like poo.

some have argued that the puter zeroes out the TPS at start up (IIRC, Stang and Two Birds is one person whom said that, and i respect what he says).

now if the car is having trouble just at idle, or with ancillary components on while at idle (i.e., a/c especially), that suggests the IAC. it is the cylinder lookin deal on the front of the TB. it lets air through the TB. one can check it with a dwell meter, but that is kinda impractical. if you want, clean it out. if it is restricted, that can cause problems.

some folks have run without it connected. i dont recommend it. they generally have to set the idle to 1000 or 1100 RPM to accomodate a/c load, etc.

i would really check out the IAC if you have not.
good luck.

 

mustangsquared

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new bern nc

Apr 7, 2004

#20

• Apr 7, 2004

• #20

My idle goes nuts when I have the heater on...bonces everywhere. I reset the TPS and the timing. Checked the Idle screw on TB (it was good to go). Any ideas.